What exactly do you want? You already got the value there in your beforeSend. You want to add your own value? Just do it then.

If you want me to help, you have to be a bit more specific about what exactly is causing you trouble.

On a side note: The parameter msg has to hold the selector string for your container DOM element. Why on earth would you call that "msg"?

Also, do you have any good reason to use synchronous AJAX?

Oh, interesting. Just when I wrote "synchronous AJAX" I threw up a little.

Again.

I think I answered that question.
I really don't know because i am new to the jquery scene, I was just trying to get with trial an error.
I also don't know why i used synchronous, I guess i'll switch it.

What is triggering your ajax call? A form submit event? Why are you using $.ajax rather than $.get or $.post?

I think you're making this harder than it is. Get the value of your input field first (and give your field an ID attribute, save the browser some work), use that to create your parameters to send to the processing page, and fire a nice, normal $.get request without all this mucking about trying to modify values in an XMLHTTP request on the fly.